USB Driver

  Can be mapped into several different functional interfaces.
   - USB-AT port
   - USB-DM port
   - USB-NMEA port
   - USB-Modem port
   - USB-Network adapter 

In QuecOpen, the GNSS NMEA is outputted to applications through a virtual serial port (/dev/smd7).

USB Design Suggestions:

For downloading → DM port
For Capturing system log→ DM port
For debugging → ADB port
For USB data channel→ /dev/ttyGS0

Add USB virtual port

diff -uprN ql-ol-sdk_ori/ql-ol-kernel/drivers/usb/gadget/android.c ql-ol-sdk/ql-ol-kernel/drivers/usb/gadget/android.c
--- ql-ol-sdk_ori/ql-ol-kernel/drivers/usb/gadget/android.c	2019-02-22 15:04:37.000000000 +0800
+++ ql-ol-sdk/ql-ol-kernel/drivers/usb/gadget/android.c	2019-06-04 18:53:04.325676077 +0800
@@ -2020,7 +2020,7 @@ static struct android_usb_function qdss_
 };
 
 /* SERIAL */
-#define MAX_SERIAL_INSTANCES 4
+#define MAX_SERIAL_INSTANCES 5
 struct serial_function_config {
    int instances_on;
    struct usb_function *f_serial[MAX_SERIAL_INSTANCES];
diff -uprN ql-ol-sdk_ori/ql-ol-kernel/drivers/usb/gadget/function/f_serial.c ql-ol-sdk/ql-ol-kernel/drivers/usb/gadget/function/f_serial.c
--- ql-ol-sdk_ori/ql-ol-kernel/drivers/usb/gadget/function/f_serial.c	2019-02-22 15:04:37.000000000 +0800
+++ ql-ol-sdk/ql-ol-kernel/drivers/usb/gadget/function/f_serial.c	2019-06-04 18:56:52.535903240 +0800
@@ -44,7 +44,7 @@
 #define GSERIAL_SET_XPORT_TYPE_SMD 1
 
 #define GSERIAL_BUF_LEN  256
-#define GSERIAL_NO_PORTS 3
+#define GSERIAL_NO_PORTS 4
 
 struct ioctl_smd_write_arg_type {
    char		*buf;
@@ -330,12 +330,16 @@ int gport_setup(struct usb_configuration
    pr_debug("%s: no_tty_ports: %u no_smd_ports: %u no_hsic_sports: %u nr_ports: %u\n",
        __func__, no_tty_ports, no_smd_ports, no_hsic_sports, nr_ports);
 
+    /* add usb channel */
    if (no_tty_ports) {
-		for (i = 0; i < no_tty_ports; i++) {
-			ret = gserial_alloc_line(
+		for (i = 0; i < GSERIAL_NO_PORTS; i++) {
+            if (gserial_ports[i].transport == USB_GADGET_XPORT_TTY)
+            {
+			    ret = gserial_alloc_line(
                    &gserial_ports[i].client_port_num);
-			if (ret)
-				return ret;
+			    if (ret)
+				    return ret;
+            }
        }
    }
 
diff -uprN ql-ol-sdk_ori/ql-ol-rootfs/sbin/usb/compositions/9025 ql-ol-sdk/ql-ol-rootfs/sbin/usb/compositions/9025
--- ql-ol-sdk_ori/ql-ol-rootfs/sbin/usb/compositions/9025	2019-02-22 16:01:26.000000000 +0800
+++ ql-ol-sdk/ql-ol-rootfs/sbin/usb/compositions/9025	2019-06-04 18:51:44.274980430 +0800
@@ -107,6 +107,7 @@ run_9607() {
    QUEC_USB_VID=2C7C
    QUEC_ENABLE_USB=0
    QUEC_USB_NET_TYPE="rmnet"
+    QUEC_USB_TTYGS1=1
    QUEC_MANUFCTURE="Quectel, Incorporated"
     QUEC_PRODUCTINFO="LTE Module"
    usb_dir="/data/usb"
@@ -190,7 +191,12 @@ run_9607() {
    echo 239 > /sys/class/android_usb/android$num/bDeviceClass
    echo 2 > /sys/class/android_usb/android$num/bDeviceSubClass
    echo 1 > /sys/class/android_usb/android$num/bDeviceProtocol
-	echo $SERIAL_FUNC > /sys/class/android_usb/android0/f_serial/transports
+    #juson.zhang-2019/06/04:add usb channel
+    if [ $QUEC_USB_TTYGS1 -eq 0 ];then
+	    echo $SERIAL_FUNC > /sys/class/android_usb/android0/f_serial/transports
+    else
+        echo $SERIAL_FUNC,tty > /sys/class/android_usb/android0/f_serial/transports
+    fi
    echo QTI,BAM_DMUX > /sys/class/android_usb/android0/f_rmnet/transports
    echo BAM_DMUX > /sys/class/android_usb/android0/f_usb_mbim/mbim_transports
    echo $USB_FUNC,ffs > /sys/class/android_usb/android$num/functions